public void DecreaseKey_WhenIndexIsInQueue_WillChangeOldKeyToNewSmallerKey()
{
IndexMinPriorityQueue <double> queue = new IndexMinPriorityQueue <double>(10);
queue.Insert(4, 12.5);
queue.Insert(3, 40.12);
queue.Insert(7, 4.3);
queue.Insert(2, 162.75);
double newKey = 5.54;
queue.DecreaseKey(3, newKey);
double keyAtIndex = queue.KeyAt(3);
Assert.AreEqual(newKey, keyAtIndex);
}
private void Relax(DirectedEdge edge)
{
uint v = edge.From;
uint w = edge.To;
if (_distanceTo[w] > _distanceTo[v] + edge.Weight)
{
_distanceTo[w] = _distanceTo[v] + edge.Weight;
_edgeTo[w] = edge;
if (_priorityQueue.Contains((int)w))
{
_priorityQueue.DecreaseKey((int)w, _distanceTo[w]);
}
else
{
_priorityQueue.Insert((int)w, _distanceTo[w]);
}
}
}